Let us return, now, to where I was in my researches.
It remains, then, for me to specify the true meaning of the shoulders in the expression of the passions. Their intervention in all forms of emotion being proven to me, it would seem that the very frequency of that intervention should exclude the possibility of assigning any particular role to this agent.
Fancy my perplexity, placed face to face with an organ infinitely expressive, but whose physiognomy is mingled promiscuously with every sentiment and every passion!
How, then, are we to characterize the shoulder? What name shall we give to its dominant rôle? How specify that supreme power outside of which all expression ceases to exist? Is it allowable for me to call it neutral? And if the universal application of that agent apparently authorizes that appellation up to a certain point, whence comes its importance? Whence the empire that it exerts over the aspect of its congeners? Is it admissible for a neutral agent to exert so much action upon the totality of the forces to which it is allied?
Assuredly not! The word neutral, moreover, excludes the idea of action, and even more strongly that of predominant action which belongs surpassingly to the shoulder. Truly, here was a treasure-house for me. It was, as they say, "to give speech to the dogs."
This new difficulty only increased the determination with which I had pursued my researches; and with the confidence arising from the fact that no obstacle had yet conquered me, I said to myself that the solution of this problem would be due to my perseverance. I could not, in view of the importance of its expression, consider the shoulder as a neutral agent. After spending a long time in vain study, I was on the point of giving up as insoluble the problem that I had set myself. Let us see by what simple means I obtained the solution. How much trouble and pains one will sometimes give himself in looking for spectacles that are on his nose!
The shoulder, in every man who is moved or agitated, rises sensibly, his will playing no part in the ascension; the successive developments of this involuntary act are in absolute proportion to the passional intensity whose numeric measure they form; the shoulder may, therefore, be fitly called the thermometer of the sensibility.
"Thermometer," I cried, "there is an excellent word, strikingly correct. But have I not, in pronouncing it, simply and naturally characterized the rôle that I am striving to define?
"Thermometer of the sensibility! Is not that the solution of the enigma? Thermometer; yes, that is it! That is the very expression to give to my researches, an expression without which nothing could be explained. That, indeed, answers to everything, and makes the difficulties against which my reason struggled disappear."
The shoulder is, in fact, precisely the thermometer of passion as well as of sensibility; it is the measure of their vehemence; it determines their degree of heat and intensity. However, it does not specify their nature, and it is certainly in an analogous sense that the instrument known by the name of thermometer marks the degrees of heat and cold without specifying the nature of the weather--a specification belonging to another instrument, the complement of the thermometer--the barometer. The parallel is absolute, perfect.